Why it happens
Shopify's privacy settings decide who is asked. In your customer privacy settings you choose in which regions shoppers see a consent banner and what happens for shoppers elsewhere. A shopper who declines must not be tracked for that purpose, so their purchase does not reach Meta or GA4 from the browser. When the banner asks shoppers everywhere and not only where the law requires it, you lose purchases you did not need to lose.
The choice may never reach Shopify. Shopify keeps one record of each shopper's choice and apps read it through the Customer Privacy API. A consent tool that shows a banner but does not pass the answer to that API leaves Shopify with a shopper who has made no choice. In the regions where you ask for consent, apps that go by Shopify's record then treat the shopper as not consented and send nothing for that purchase. Whether a more permissive mode is right for your markets is your decision as the store owner.
Shoppers ignore the banner. Some shoppers close the page, scroll past the banner or never answer. Those purchases carry no consent either way. How they are handled depends on the mode of your tracking and on your region. A lower count after a new banner is partly this and is normal.
Two banners can also fight each other: a theme's banner and an app's banner, each saving a different answer. The record that wins decides what your tracking sees.
Check it yourself
- 1In Shopify admin, open Settings, then Customer privacy. Look at the cookie banner section and note in which regions shoppers are asked and which are not.
- 2Compare that with where your shoppers live. If you sell mostly outside the regions that require consent, check whether your banner needs to ask there at all. Use legal advice for your markets, not a guess.
- 3Open your consent tool's settings and check that it is set up for Shopify and passes the shopper's choice to Shopify's Customer Privacy API. Its help page tells you whether it does. For Google tags, see Consent Mode v2 with Shopify's banner.
- 4Check that only one banner runs. Open your store in a private window and look. Two banners mean two records.
- 5In your consent tool, compare the share of shoppers who accepted, declined or did not answer. A large share that did not answer says the banner is not seen or not understood.
- 6In Shopify admin, open Settings, then Customer events, and look at the list of pixels and their status. A pixel that is not connected, or a custom pixel that waits for a consent state, can explain missing purchases too.
- 7Open Meta Events Manager, Data sources, your pixel, and compare the Purchase count before and after the date you changed the banner. In GA4, open Reports, then Monetization, then Ecommerce purchases, and compare the same periods. A drop on the day of the change points to consent.
- 8Test it. Open your store in a private window, decline the banner, place a test order, and see whether the purchase appears in Events Manager's Test events tab. Then repeat it with Accept.
A server sender applies the same choice in the consent mode you pick; see Shopify server-side tracking.
FAQ
Is a drop after a banner a bug?
Not by itself. A shopper who declines is not tracked, so the count falls by their share. It is a bug when shoppers who accepted are also missing.
Can I switch the banner off to get the purchases back?
That is a legal question for your markets, and it is your decision as the store owner. Check the rules that apply to your shoppers first.
Do GA4 and Meta need the same consent?
No. Meta uses marketing consent and GA4 uses analytics consent, so one shopper can be sent to one and not to the other.
Why do my orders in Shopify not change?
Consent decides what is reported to platforms, not whether a shopper can buy. Your orders stay the same.